feat: not found page

src/app/not-found.tsx

@@ -0,0 +1,15 @@
+export default function NotFound() {
+  return (
+    <>
+      <section className="section section-md bg-default text-center">
+        <div className="container">
+          <h2 className="text-spacing-20">Page Not Found</h2>
+          <p className="heading-5">You may have mistyped the address or the page may have moved</p>
+          <a className="button button-primary" href="/">
+            Go to Homepage
+          </a>
+        </div>
+      </section>
+    </>
+  );
+}